Add string view overloads (#1154)

This is better ergonomic, as `std::string_view` is lightweight and accept more conversion than `const std::string&`.

Co-authored-by: ArthurSonzogni <sonzogniarthur@gmail.com>

include/ftxui/dom/canvas.hpp

@@ -106,9 +106,9 @@ struct Canvas {
   // Draw using character of size 2x4 at position (x,y)
   // x is considered to be a multiple of 2.
   // y is considered to be a multiple of 4.
-  void DrawText(int x, int y, const std::string& value);
-  void DrawText(int x, int y, const std::string& value, const Color& color);
-  void DrawText(int x, int y, const std::string& value, const Stylizer& style);
+  void DrawText(int x, int y, std::string_view value);
+  void DrawText(int x, int y, std::string_view value, const Color& color);
+  void DrawText(int x, int y, std::string_view value, const Stylizer& style);
 
   // Draw using directly pixels or images --------------------------------------
   // x is considered to be a multiple of 2.

include/ftxui/dom/elements.hpp

@@ -7,6 +7,7 @@
 #include <functional>
 #include <memory>
 
+#include <string_view>
 #include "ftxui/dom/canvas.hpp"
 #include "ftxui/dom/direction.hpp"
 #include "ftxui/dom/flexbox_config.hpp"
@@ -51,8 +52,8 @@ Elements operator|(Elements, Decorator);
 Decorator operator|(Decorator, Decorator);
 
 // --- Widget ---
-Element text(std::string text);
-Element vtext(std::string text);
+Element text(std::string_view text);
+Element vtext(std::string_view text);
 Element separator();
 Element separatorLight();
 Element separatorDashed();
@@ -61,7 +62,7 @@ Element separatorDouble();
 Element separatorEmpty();
 Element separatorStyled(BorderStyle);
 Element separator(Pixel);
-Element separatorCharacter(std::string);
+Element separatorCharacter(std::string_view);
 Element separatorHSelector(float left,
                            float right,
                            Color unselected_color,
@@ -89,11 +90,11 @@ Decorator borderStyled(Color);
 Decorator borderWith(const Pixel&);
 Element window(Element title, Element content, BorderStyle border = ROUNDED);
 Element spinner(int charset_index, size_t image_index);
-Element paragraph(const std::string& text);
-Element paragraphAlignLeft(const std::string& text);
-Element paragraphAlignRight(const std::string& text);
-Element paragraphAlignCenter(const std::string& text);
-Element paragraphAlignJustify(const std::string& text);
+Element paragraph(std::string_view text);
+Element paragraphAlignLeft(std::string_view text);
+Element paragraphAlignRight(std::string_view text);
+Element paragraphAlignCenter(std::string_view text);
+Element paragraphAlignJustify(std::string_view text);
 Element graph(GraphFunction);
 Element emptyElement();
 Element canvas(ConstRef<Canvas>);
@@ -120,8 +121,8 @@ Element bgcolor(const LinearGradient&, Element);
 Decorator focusPosition(int x, int y);
 Decorator focusPositionRelative(float x, float y);
 Element automerge(Element child);
-Decorator hyperlink(std::string link);
-Element hyperlink(std::string link, Element child);
+Decorator hyperlink(std::string_view link);
+Element hyperlink(std::string_view link, Element child);
 Element selectionStyleReset(Element);
 Decorator selectionColor(Color foreground);
 Decorator selectionBackgroundColor(Color foreground);

include/ftxui/dom/selection.hpp

@@ -30,7 +30,7 @@ class Selection {
   Selection SaturateVertical(Box box);
   bool IsEmpty() const { return empty_; }
 
-  void AddPart(const std::string& part, int y, int left, int right);
+  void AddPart(std::string_view part, int y, int left, int right);
   std::string GetParts() { return parts_.str(); }
 
  private: